Knluk My thinking is to get rid of the last part of the shot which is bitter. Does it make sense to all fellow members here?
You are free to do whatever works for you, but no, discarding the last part of the shot makes no sense. Just pull a shorter shot if that is what want.
In a balanced shot, even if the last part of the output is weaker & bitter, the shot will still be good, because the early part will be under-extracted & sour, even if you kill the shot when the last drops taste good on their own (this is something I have explored in the past - discarding 1st drips, discarding last part).
Why not just make 3 more shots at 1.7.3, 18.2gin, 37.1g out and ensure that they are consistent?
I’m a bit confused by your scoring and analysis, you are scoring out of 10, so 5.5 would be neutral, neither like nor dislike, 6.5 would then be a positive score in that it was likeable, but you have had better & know there is room for improvement, yet you say, “But this shot is marginally drinkable. I don’t enjoy it much”? 6.5 might be a score I’d give to representative shot of mass market espresso blend, where I’d be perfectly happy with it in context and I wouldn’t ever expect a 9 from it.
The scores of 5.4 to 5.6 are all essentially the same thing, differences of +/-2%, which are inseparable from noise. Try and simplify the scoring & make a call to keep to whole digits, or 0.5 intervals.
